In the spring of 1993 Ross Secord contacted Richard Hilton of the Sierra College Geology department with a request to help excavate a fossil mammal he had found in a blowout basin on the southeast end of “The Island,” a peninsula in Honey Lake, in southeast Lassen Co., California. His few pieces had been tentatively identified by a paleontologist at Berkeley as a musk or shrub ox. Mr. Hilton and Charles Dailey accompanied Ross to the site on Memorial Day weekend 1993 and excavated the animal.
Taphonomy
It was laying on its left side with its legs outstretched and was apparently originally preserved fully intact. The right side of the skeleton shows slightly more deterioration than the left and the right side of individual bones show more deterioration than the left. There is about 5 inches of biotite mica and quartz sand under the deer. The burial layer is mostly sand and mica, derived from Sierran sources to the west, with particle size coarsening upward, occasionally up to a centimeter (1/2 inch) in diameter. It was deposited in a relatively short time with a water flow more energetic than typical for the clay sediments of the lake basin below. The burial layer extends for the entire kilometer or more length of the blowout basin. Perhaps tectonic uplift along the Honey Lake Fault and/or the east edge of the Sierra Nevada moved the stream inflow eastward and/or drying climate lowered the lake level. There is a 1 to 2 inch thick, red hard pan layer about 6 inches above the deer. This may have formed some time later. Some fossilized roots in the sandy layers above the deer are yellow and look fresh enough to burn but only turn rusty red when fired. No evidence has yet been discovered to determine when these grew in the burial layer. Small, pink, double ended crystals of ??? are scattered throughout the sediment layer.
Excavation
The cannon bone (fused 3rd and 4th metatarsals) of the hind foot was too long and slender to be a stocky musk ox or even an extinct shrub ox. The closed, anterior, distal, metatarsal gully also found in two families of mammals; the deer (Cervidae) or American pronghorn (Antilocapridae) families. American pronghorns are highly adapted for rapid running on hard ground and have no dewclaws (small side toes) to slow down their foot movements. The fossil had dewclaws, so it belongs to the deer family.
Small Elk or Large Deer?
Mathematical scaling from the hind foot indicates it weighed about 260 kilograms (580 pounds) when alive. So the fossil “What’sit” is as large as a large female California tule elk (Cervus). But it has a male pelvis. The growth plates on the feet were fully fused, so it was a full grown, adult animal. Could it be a small California tule elk adapted to survive on sparse desert vegetation? Mule deer (Odocoileus) occasionally weigh up to 300 pounds. Could it be a gigantic mule deer from the Pleistocene Ice Age when animals were commonly larger to better withstand the effects of the cold? How can you distinguish a large Odocoiline deer from a small Cervine elk? Deer have small medial and lateral metacarpal bones which attach to the small dewclaws (lateral toes) of the front feet, but elk have even smaller metacarpals that are near the top of the front feet, detached from the dewclaws a few inches lower. Further excavation revealed that this animal has relatively large medial and lateral metacarpals attached to the lateral toes. Therefore it is a deer, a LARGE deer!
Morphology
Could this “What’sit” deer be the world record Mule deer, or is it a Whitetail or one of the larger Ice Age species that recently became extinct, such as Navahoceros from the southwestern United States and Mexico? Most deer are classified by their antler shape. Luckily this was a male. So what is on the head (anterior) end of the skeleton? Unfortunately there is a gully which eroded through the head and neck and exposed the pieces that Ross found. Screening from the outwash apron down the gully below the fossil did not reveal any antler pieces. Could someone have found this fossil site before Ross and taken the antlers home for a souvenir? Perhaps it died during the winter or early spring after its antlers had fallen off and before the next set started to grow. That is the time of year when most animals die. So how do we determine what species it is?
The next best identifying features are the teeth. They are the hardest and some of the most durable parts of the animal, and a few were found on the outwash apron. Screening produced some more pieces. And back at the burial site the screening produced a canine tooth. The lower canine teeth of deer are just behind the front incisors and modified to function like the incisors for browsing vegetation from bushes and trees. But this was a relatively large upper canine tooth! It was 3 cm or 1 1/4" long! This size of upper canine tooth is not found in living species of American deer. But a pair of large upper canine teeth are found in primitive male Asian deer. Altogether we have a least one example of about 82% of the teeth types. The molars are large and worn. It was probably at least 7 years old when it died. The extinct Odocoileus brachyodontus was defined by the dentine on the adjacent, lateral halves of the upper molars not touching. In this deer even the lateral enamel of the two molar halves are separated. It is significantly more primitive than living or fossil North American Odocoileus deer.
Systematics
So now it is necessary to compare the parts we have with equivalent parts of the living and extinct species of deer to determine its closest relatives. Dailey contacted Dr. Victor Morejohn in Oregon who has been studying the post-cranial anatomy of living North American deer for the last few years. He was happy to assist. It isn't either of the living North American deer. And it isn't a moose (Alces) or a living caribou (Rangifer) or an elk (Cervus). Of the living deer it is most similar to the living Mule and Whitetail deer, Odocoileus.
Charles also visited the Field Museum in Chicago to compare it with South American deer. Then he went to the American Museum in New York, the Smithsonian, the Academy of Sciences in Philadelphia and the Idaho State University to compare it with extinct species. Well, there is a bump on the inner and outer side of the rear knuckles. It hasn't been found on any of the other living or extinct deer. There isn't anything like this in any collections we know of. This seems to be something unique. But some of the fossil deer are only known from a few pieces other than the metatarsals. So detailed comparisons of each of the known fossil species still needed to be made. When possible that is in progress. Students are also returning to the site to look for more parts, especially antlers. Apparently parts of 3 to 6 deer have been found so far, but still no antlers.
Antlers?
The small Asian Roe deer has a small fork on the antlers and upper canine teeth. Mature, living North American male deer typically have four points on each side and a small brow tine or eye guard. If we found antlers, what would a mature set from this primitive deer probably look like? The best guesses would be either a large Y-shaped fork, or more likely three points, a fork and a single tine on each side, with a small forward projecting brow line.
Bretzia or Torontoceros?
Bretzia is the earliest known member of the deer family in North America, ranging from about 4 million years ago (Pliocene) to the recent past. So our deer could have come here across the Bering Straits from Asia at least as long ago as 4 million years. Torontoceros, presumably a caribou, is known only from one Ice Age specimen. Both genera were described only from antlers. So there is presently no known way to anatomically compare “What’sit” with Bretzia or Torontoceros. Our deer and the early Bretzia are probably both too old to extract DNA and compare. However DNA from two recent Bretzia specimens from Nebraska, Navahoceros from Mexico and Torontoceros from Canada could be compared with the living deer and caribou (Rangifer). That is the plan for this year's research.
Life Style?
What did the deer do for a living? Good runners typically have long, lightweight feet and toes for long, quick strides. Good jumpers have shorter more powerful bones. Soft ground animals commonly have large toes and hooves to support them. Did it wander the edge of marshy lakes like the Pere David's swamp deer of Asia (Elaphurus) or the Moose (Alces)? Or did it run across a soft muskeg and tundra-like or woodland environments during the Ice Age like the Caribou? Was it an upland jumping species like the modern Mule deer which was forced down to the less snowy valley floor during harsh winter? Or was it a running deer that lived in forests like the living Whitetail? All of these are real possibilities. To determine this it is necessary to compare the proportions of the various limb bones to discover their specific adaptations. This analysis has not been done yet.
Community Ecology
Also in the area we have many red oxidized layers with parts of fish that died when the nearby lake dried up and became too salty or alkaline. These are 1 to 2 meters under the deer. Also we have found claws of a predatory bird that either ate the fish (an osprey?) or a hawk or owl that ate the local rabbits and/or rodents, an ankle and tibial bone of an 80 pound wolf, parts of a couple of horses, a piece of mastodon and many snails. We can begin to reconstruct the ecology of the area. The fish mortality layers in red oxidized sand and biotite mica sediment suggest a dry period similar to current climate. Soil analysis revealed pollen similar to the present vegetation. Fossil rodents would be ideal for determining the local ecological conditions. A mole femur found recently may be useful.
Biogeography
Some of the fish (and snails?) are not the present Great Basin species but are similar (if not identical to) those which live in the Snake River drainage to the north. Some parts of our same deer have been found in Pliocene deposits of Lake Idaho in the western end of the Snake River plain. And a sacrum of a large cervid was found by Mr Hilton east of Clear Lake, California. It looks like our same deer. It needs to be cleaned and thoroughly studied. Rear foot (metatarsal) bones from cave deposits in north east Mexico are stored in the Los Angeles County Museum. Some of them have the unusual bumps on the sides of the knuckles (trochlea). So we are beginning to determine the geographic range of this species.
Geologic Age?
How old is this animal? The area was mapped as Quaternary, Pleistocene or more recent. It is in the Ice Age Lake Lahontan basin and the area was under 350 feet of lake water during the last Ice Age. Three authorities have visited the site and given three different opinions of the sediment age; from Pleistocene to Pliocene. The area is a few miles east of the Honey Lake fault and a few hundred meters west of the Warm Springs Valley fault. The local drainages washed in about one to two meters of granitic sand and biotite mica that contains the deer. Under this is approximately 1800' to 2000' of sediment. This has occurred since the beginning of the Great Basin spreading. The area is seismically active and had a 6.0 earthquake in 1875. The basin is part of a breached, faulted anticline. Like Sand Mountain east of Fallon, Nevada, the canyons to the east show evidence of having been buried in wind blown sand during past desert climate periods. This helps account for the missing local layers. The strata tilt at the north end of "The Island" is about 15 degrees to the northwest. If this tilt is consistent the blowout basin would be older that the north end of the island.
John Fortuna, while a senior at C.S.U. Sacramento, located a volcanic ash (tephra) in clay sediments about a meter below the deer. Is is being analyzed at the U.S. Geological Survey in Menlo Park, California with an ion microprobe to determine the detailed chemical composition. Hopefully it can be correlated with a tephra of known age. If not they will have to melt crystals with an argon laser to release radioactive gasses in order to analyze them and determine the tephra age. The deer is slightly younger than the tephra. The thinly bedded clay layers accumulated relatively slowly. The sediment layers at Tule Lake accumulated at about 1 meter per 10,000 years. This is about 1 centimeter per century or 0.1 millimeter per year. So our deer may be a few thousand years younger than the tephra. There was a poorly known magnetic reversal during the time these sediments were deposited. Dr. Kenneth Verosub, of U.C. Davis, has found residual magnetism in the sediments of the area and may want to study the magnetism of the layers.
Hopefully this giant deer, apparently previously unknown, will be studied, diagnostic teeth and bones illustrated, the animal described, named, its closest relatives and its geologic age finally determined and submitted for publication in The Journal of Vertebrate Paleontology sometime soon.
2000 Update
This deer has now been compared with the holotype toe and ankle bones of the extinct Cervus lucasi (Hay 1927) from southeast Idaho. They are stored at the Smithsonian National Museum. This deer was about 1.5 to 2.0 million years old, and the toe and ankle are identical to the Honey Lake deer. But the rest of the Honey Lake deer bones indicate it is not an elk (Ceruvs), but the extinct ancestor of modern Odocoileus, Blacktail and Mule deer. So its name has to be changed to Odocoileus lucasi (Hay 1927).
Natural History Museum Publication
The Identity and Postcranial Osteology of Odocoileus Lucasi (Hay) 1927: A Plio-Pleistocene Deer from California and Idaho by G. Victor Morejohn and D. Charles Dailey